In the field of shipping containers there is a series of platform based cargo carriers called collapsible flatracks comprising a platform base with erect posts normally at each end though sometimes toward the middle. The posts fold down onto the base to allow the folded flatracks to be stacked one upon another for economical transport and storage. Such collapsible flatracks have been around for decades and are described in many an earlier patent. It is sometimes desired to load the flatrack from one end rather than from the side.
The posts are typically rather too heavy for man handling and so are normally filled with counterbalance springs or other resilient biassing to enable the posts to be folded and erected manually.
The walls or posts pivot on fairly substantial pivot pins, and over the years, these pins begin to corrode or seize up with dirt. Thus their removal from engagement with the post hinge elements after some time can be problematical.
During the operation of the wall, it is important that personnel and cargo are not hurt.